Ultrathin DNA–copper nanosheets with antibacterial and anti-biofilm activity for treatment of infected wounds

Abstract

The development of innovative antibacterial materials is crucial for addressing wounds infected with bacterial biofilms. Advanced nanomaterials that enable non-antibiotic antibacterial strategies offer new possibilities for treating bacterial infections by eliminating pathogens without relying on antibiotics. Herein, we introduce non-toxic and biocompatible DNA–copper cluster nanosheets (DNS/CuNCs) as effective antibacterial agents. DNS/CuNCs can reduce bacterial surface motility and the secretion of virulence factors by interfering with quorum sensing, and thereby inhibit biofilm formation and enhance their potential as prophylactic antibacterial agents. Notably, DNS/CuNCs exhibit significant in vitro bactericidal activity against Staphylococcus aureus and Pseudomonas aeruginosa and disrupt established surface biofilms in the presence of hydrogen peroxide (H₂O₂). This is attributed to the synergistic effects of their physical ultrathin properties and peroxidase-like activity, which lead to an increase in intracellular ROS levels in bacteria, thereby achieving antibacterial and biofilm-disrupting effects. In vivo, DNS/CuNCs effectively eradicate bacterial infections, promote wound healing, and restore normal tissue morphology without toxicity to mammalian cells. With their combined abilities to inhibit biofilm formation, exhibit antibacterial activity, and disrupt biofilms, along with excellent biocompatibility, DNA-templated CuNCs emerge as highly promising candidates for preventive and clinical antibacterial therapies.